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Comparative study on the hydrogen storage performance of as-milled MgRENi rapid quenched alloy catalyzed by metal sulfides

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Journal of Magnesium and Alloys 2024年第5期12卷 2010-2023页

作者： Xiaoping Dong Zhaoqing Zhang liying Yang Shenghai Xin Dandan Su zhiyuan li Department of Mechanical Design and Manufacture and Automation Hebei University Baoding New Energy Vehicle Power Engineering Technology Research Center Hebei University Hebei Technology Innovation Center for lightweight of New Energy Vehicle Power System(Preparation) Hebei University

The composites of Mg20Pr1Sm3Y1Ni10as-quenched alloy and 3 wt.% M（M = CoS, CoS2, MoS2） catalyst were prepared by high-speed vibration ball mill. The effects of metal sulfides on the hydrogenation and dehydrogenation dynamics of alloys were compared. The results show that the as-milled composites contain a large number of amorphous embedded by a small amount of nanocrystals, and there are many point defects. After ball milling, the crystal grain size in the composites containing CoS is relatively larger, followed by CoS2and MoS2again. After hydrogenation, the amorphous phase is crystallized to form Mg2NiH4, YH3, Pr8H18.96, Sm3H7, Mg, Co or Mo phases, however,Mg2Ni, YH2, PrH2and Ni3Y phases appeared after dehydrogenation. The maximum hydrogenation capacity of the composites containing CoS, CoS2and MoS2are 3.939, 4.265 and 4.507 wt.%, respectively. The hydrogenation saturation ratio of composite containing MoS2is higher than that of the composites containing CoS and CoS2. The dehydrogenation activation energy of the composites containing CoS, CoS2and MoS2is 107.76, 68.43 and 63.28 kJ.mol-1.H2. On the improvement of hydrogen storage performance of Mg20Pr1Sm3Y1Ni10alloy, the catalytic effect of MoS2sulfide is better than that of CoS2sulfide, and which is better than CoS sulfide.

关键词： Mg 20 Pr 1 Sm 3 Y 1 Ni 10 as-quenched alloy CoS CoS 2 and MoS 2 sulfide Milling Activation energy Hydrogen storage dynamics

MnO-pillared graphene blocks enabling the ultrastable and ultrafast aqueous zinc ion batteries

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Science China Chemistry 2024年

作者： Zheng liu Zhipeng Qiu zhiyuan li Tong Wei Zhuangjun Fan Huan Pang School of Chemistry and Chemical Engineering Yangzhou University School of Materials Science and Engineering China University of PetroleumQingdao

Due to the low cost, high theoretical capacity, and environmental friendliness, manganese-based cathodes are regarded as promising alternatives for aqueous zinc ion batteries（AZIBs）. However, the practicality of the zinc-manganese system is faced with great challenges, such as the inevitable structural collapse of the cathode and controversial energy storage mechanisms.Herein, we propose a novel concept of spatial deposition mechanism through the addition of MnSO4additives in the MnOpillared graphene blocks（G-MnO）. The covalent interface between MnO nanoparticles and multilayered graphene nanosheets can construct an in-built micro-electric field, which is beneficial for consecutive electron transfer（in both horizontal and vertical directions）. On this basis, the surficial activity of MnO confined in the interlayered nano-space is greatly enhanced and provides enough spatial deposition and subsequent reaction site for MnSO4additives, thus firstly extending the surficial controlled process to stereoscopic space, effectively improving the electrochemical performance of AZIBs. Therefore, the assembled Zn//G-MnO battery exhibits an excellent rate capability of 281.5 mAh g-1at 0.1 A g-1and 106 m Ah g-1at 20 A g-1, and impressive cycling stability(93 m Ah g-1remaining after 5,000 cycles). This finding may provide a new opportunity for the rational design of surficial controlled energy storage and conversion devices.

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A Fermi-LAT Study of Globular Cluster Dynamical Evolution in the Milky Way:Millisecond Pulsars as the Probe

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Research in Astronomy and Astrophysics 2024年第2期24卷 1-23页

作者： li Feng Zhongqun Cheng Wei Wang zhiyuan li Yang Chen School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Department of Astronomy School of Physics and TechnologyWuhan UniversityWuhan 430072China WHU-NAOC Joint Center for Astronomy Wuhan UniversityWuhan 430072China Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityNanjing 210023China

Using archival Fermi-LAT data with a time span of~12 yr,we study the population of Millisecond Pulsars(MSPs)in Globular Clusters(GlCs)and investigate their dependence on cluster dynamical evolution in the Milky Way.We show that theγ-ray luminosity(L_(γ))and emissivity(i.e.,ε_(γ)=L_(γ)/M,with M the cluster mass)are good indicators of the population and abundance of MSPs in GlCs,and they are highly dependent on the dynamical evolution history of the host clusters.Specifically speaking,the dynamically older GlCs with more compact structures are more likely to have larger L_(γ)andε_(γ),and these trends can be summarized as strong correlations with cluster stellar encounter rateΓand the specific encounter rate(Λ=Γ/M),with L_(γ)∝Γ^(0.7±0.11)andε_(γ)∝Λ^(0.73±0.13)for dynamically normal GlCs.However,as GlCs evolve into deep core collapse,these trends are found to be reversed,implying that strong encounters may have lead to the disruption of Low-Mass X-ray Binaries and ejection of MSPs from core-collapsed systems.Besides,the GlCs are found to exhibit largerε_(γ)with increasing stellar mass function slope(ε_(γ)∝10^((0.52±0.1)α)),decreasing tidal radius(ε_(γ)∝R_(t)^(-10±0.22))and distances from the Galactic Center(GC,ε_(γ)∝R_(gc)^(-1.13±0.21)).These correlations indicate that,as GlCs losing kinetic energy and spiral in toward the GC,tidal stripping and mass segregation have a preference in leading to the loss of normal stars from GlCs,while MSPs are more likely to concentrate to cluster center and be deposited into the GC.Moreover,we gaugeε_(γ)of GlCs is~10-1000 times larger than the Galactic bulge,the latter is thought to reside thousands of unresolved MSPs and may be responsible for the GC 7-ray excess,which supports that GlCs are generous contributors to the population of MSPs in the GC.

关键词： (Galaxy:)globular clusters general-(stars:)pulsars general-Galaxy kinematics and dynamics-Galaxy center-Galaxy bulge-gamma-rays stars-gamma-rays diffuse background-gamma-rays galaxies

Price Masking Strategy of Cross-Border E-Commerce Platform Financing

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Journal of Systems Science & Complexity 2024年第2期37卷 668-691页

作者： li Jianbin HANG Zhouxin CHEN zhiyuan XIAO Shan School of Management Huazhong University of Science and TechnologyWuhan 430074China School of Economics and Management Wuhan UniversityWuhan 430072China

E-commerce platform financing is a new service pattern of supply chain finance.However,this pattern may bring some new issues when considering the problem of cash flow shortage and financing difficulties of small and medium-sized enterprises.When enterprises use this service,they worry about the leakage of preferential wholesale price when applying the full loan amount and providing the true transaction information.Based on the model consisting of a supplier,a retailer and a cross-border e-commerce platform,the authors design a price masking strategy to prevent the retailer’s preferential wholesale price information from leakage.The authors analyze the profit of the retailer and the platform before and after adopting the price masking strategy.The authors find that the price masking strategy always benefits the retailer.Besides,the optimal profit of the retailer and the platform are both affected by the loan interest rate.Moreover,there exists a range of loan interest rates that can benefit both the retailer and the platform if the price masking strategy is adopted.The research emphasizes that platform can expand the total business volume by allowing retailers to use price masking strategy.In other words,there will be more and more retailers attracted by the strategy,which benefits the long-term growth of cross-border e-commerce platform financing.

关键词： Cross-border e-commerce e-commerce platform financing price masking supply chain finance

Experimental investigation about the incipient velocity of spherical particles on a hemispherical bed surface

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Particuology 2024年第5期88卷 49-61页

作者： Chuannan li Jie Chen Changbo Jiang Xie li zhiyuan Wu School of Hydraulic and Environmental Engineering Changsha University of Science & TechnologyChangsha 410114China Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province Changsha 410114China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China

The sediment particles play a huge role in shaping the bed load transport.In this research,240 water-tunnel experiments are carried out to investigate the incipient velocity of the observation particles in two particle arrangements.To accurately predict the incipient velocity of the observation particles,the equation is conceived by the rolling instability mechanism.The incipient velocity equations and experimental data are used to analyze the trend of dispersive pressure and the effect of arrangement position on velocity.We find that it is appropriate to choose the coefficient of drag as 0.261 and the coefficient of lift as 0.198 for the incipient velocity equation of spherical particles on the hemispherical bed surface.Furthermore,the dispersive pressure is closely related to the flow state,particle size,and particle arrangement,which leads to the incipient velocity of the observation particle being at a minimum when the interference particle angle is 45°.Finally,the particle spacing and the projected area changed with the arrangements,directly affecting the incipient velocity of the observed particle.The analysis of four aspects for the coefficients,dispersive pressure,different particle spacing,and projected area will facilitate the prediction of particle incipient velocity,especially on hemispherical beds.

关键词： Hemispherical bed surface Observed particle Interference particle Dispersive pressure Incipient velocity

Pre-mating nitenpyram exposure in male mice leads to depression-like behavior in offspring by affecting tryptophan metabolism in gut microbiota

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Journal of Environmental Sciences 2024年第3期137卷 120-130页

作者： Sen Yan Wei Sun Sinuo Tian zhiyuan Meng Jinling Diao Zhiqiang Zhou li li Wentao Zhu Innovation Center of Pesticide Research Department of Applied ChemistryCollege of ScienceChina Agricultural UniversityBeijing 100193China College of Plant Protection/Joint International Research Laboratory of Agriculture&Agri-Product Safety Yangzhou UniversityYangzhou 225009China College of Plant Protection Shanxi Agricultural UniversityTaiyuan 030031China

Several studies have confirmed that the health status of the paternal affects the health of the offspring,however,it remains unknown whether paternal exposure to pesticides affect the offspring health.Here,we used untargeted metabolomics and 16S rRNA sequencing technology,combined with tail suspension test and RT-qPCR to explore the effects of paternal exposure to nitenpyram on the neurotoxicity of offspring.Our results found that the paternal exposure to nitenpyram led to the offspring’s depressive-like behaviors,accompanied by the reduction of tryptophan content and the disorder of microbial abundance in the gut of the offspring.Further,we determined the expression of tryptophan metabolism-related genes tryptophanase(tnaA)and tryptophan hydroxylase 1(TpH1)in gut bacteria and colonic tissues.We found that tryptophan is metabolized to indoles rather than being absorbed into colonocytes,which coursed the reduce of tryptophan availability after nitenpyram exposure.In conclusion,our study deepens our understanding of the intergenerational toxic effects of pesticides.

关键词： Nitenpyram Depressive-like behaviors Gut microbiota Tryptophan metabolism

Effect of particle composition and consolidation degree on the wave-induced liquefaction of soil beds

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Acta Oceanologica Sinica 2024年第2期43卷 11-22页

作者： zhiyuan Chen Yupeng Ren Guohui Xu Meng li Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Marine Ecological Restoration and Smart Ocean Engineering Research Center of Hebei Province Qinhuangdao 066000China Key Laboratory of Marine Environment and Ecology(Ocean University of China) Ministry of EducationQingdao 266100China Key Laboratory of Submarine Geoscience and Prospecting Techniques(Ocean University of China) Ministry of EducationQingdao 266100China

The wave-induced liquefaction of seabed is responsible for causing damage to marine structures.Particle composition and consolidation degree are the key factors affecting the pore water pressure response and liquefaction behavior of the seabed under wave action.The present study conducted wave flume experiments on silt and silty fine sand beds with varying particle compositions.Furthermore,a comprehensive analysis of the differences and underlying reasons for liquefaction behavior in two different types of soil was conducted from both macroscopic and microscopic perspectives.The experimental results indicate that the silt bed necessitates a lower wave load intensity to attain the liquefaction state in comparison to the silty fine sand bed.Additionally,the duration and development depth of liquefaction are greater in the silt bed.The dissimilarity in liquefaction behavior between the two types of soil can be attributed to the variation in their permeability and plastic deformation capacity.The permeability coefficient and compression modulus of silt are lower than those of silty fine sand.Consequently,silt is more prone to the accumulation of pore pressure and subsequent liquefaction under external loading.Prior research has demonstrated that silt beds with varying consolidation degrees exhibit distinct initial failure modes.Specifically,a dense bed undergoes shear failure,whereas a loose bed experiences initial liquefaction failure.This study utilized discrete element simulation to examine the microscopic mechanisms that underlie this phenomenon.

关键词： wave flume liquefaction pore water pressure consolidation permeability experiment discrete element simulation

Indefinite metacavities coupled to a mirror:bound states in the continuum with anomalous resonance scaling

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Photonics Research 2024年第3期12卷 598-607页

作者： QIANG ZHANG PEIXIANG li zhiyuan GU SHAODING liU ZEJUN DUAN College of Electronic Information and Optical Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China

Indefinite metacavities(IMCs)made of hyperbolic metamaterials show great advantages in terms of extremely small mode volume due to large wave vectors endowed by the unique hyperbolic dispersion.However,quality(Q)factors of IMCs are limited by Ohmic loss of metals and radiative loss of leaked waves.Despite the fact that Ohmic loss of metals is inevitable in IMCs,the radiative loss can be further suppressed by leakage engineering.Here we propose a mirror coupled IMC structure which is able to operate at Fabry–Pérot bound states in the continuum(BICs)while the hyperbolic nature of IMCs is retained.At the BIC point,the radiative loss of magnetic dipolar cavity modes in IMCs is completely absent,resulting in a considerably increased Q factor(>90).Deviating from the BIC point,perfect absorption bands(>0.99)along with a strong near-field intensity enhancement(>1.8×10^(4))appear when the condition of critical coupling is almost fulfilled.The proposed BICs are robust to the geometry and material composition of IMCs and anomalous scaling law of resonance is verified during the tuning of optical responses.We also demonstrate that the Purcell effect of the structure can be significantly improved under BIC and quasi-BIC regimes due to the further enhanced Q factor to mode volume ratio.Our results provide a new train of thought to design ultra-small optical nanocavities that may find many applications benefitting from strong light–matter interactions.

关键词： hyperbolic mirror definite

A novel interpretable multilevel wavelet decomposition deep network for actual heartbeat classification

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Science China Technological Sciences 2024年第6期67卷 1842-1854页

作者： JIN YanRui li zhiyuan TIAN YuanYuan WEI XiaoYang liU Chengliang School of Mechanical Engineering Shanghai Jiao Tong University

Arrhythmias may lead to sudden cardiac death if not detected and treated in time. A supraventricular premature beat(SPB) and premature ventricular contraction(PVC) are important categories of arrhythmia disease. Recently, deep learning methods have been applied to the PVC/SPB heartbeats detection. However, most researchers have focused on time-domain information of the electrocardiogram and there has been a lack of exploration of the interpretability of the model. In this study, we design an interpretable and accurate PVC/SPB recognition algorithm, called the interpretable multilevel wavelet decomposition deep network(IMWDDN). Wavelet decomposition is introduced into the deep network and the squeeze and excitation(SE)-Residual block is designed for extracting time-domain and frequency-domain features. Additionally, inspired by the idea of residual learning, we construct a novel loss function for the constant updating of the multilevel wavelet decomposition parameters.Finally, the IMWDDN is evaluated on the Third China Physiological Signal Challenge Dataset and the MIT-BIH Arrhythmia database. The comparison results show IMWDDN has better detection performance with 98.51% accuracy and a 93.75% F1-macro on average, and its areas of concern are similar to those of an expert diagnosis to a certain extent. Generally, the IMWDDN has good application value in the clinical screening of PVC/SPB heartbeats.

关键词： actual heartbeat classification electrocardiogram interpretable deep network multilevel discrete wavelet decomposition layer SE-Residual block